1. Field of the Invention
This invention relates generally to the field of reprocessing medical equipment. In particular, it relates to an improved device and method for sterilizing and reprocessing balloon-tipped catheters that are used in the surgical reconstruction of blood vessels.
2. Description of the Related Art
Balloon-tipped catheters were first introduced in the mid-1970's to aid surgeons in performing percutaneous transluminal angioplasty. Percutaneous transluminal angioplasty is one of the recognized methods used to treat arteries that are totally obstructed or partially occluded by plaque. Angioplasty is typically performed by making a puncture wound in the patient's thigh to gain access to the femoral artery. A guidewire is passed through the artery and advanced through the vascular system until the distal end of the wire reaches the arterial stenosis, whether iliac, femoral, femoropopliteal, aortic, renal, splanchnic, coronary or brachiocephalic. A guiding catheter is next advanced over the guidewire until its distal end passes over the distal end of the guidewire. The guidewire is then removed and a special PTA wire is advanced through the guiding catheter up to the locus of the stenotic lesion. The surgeon then manipulates the proximal end of the PTA wire to pass it through the stenotic lesion that is obstructing the artery. Next, a PTA balloon catheter is passed over the PTA wire and positioned adjacent to the stenotic lesion. Thus positioned, the balloon is inflated by injecting thereinto a bio-compatible fluid, such as saline. As the balloon inflates, it contacts and compresses the plaque forming stenotic lesion by urging it radially outward. The plaque is displaced thus restoring patency to the target artery. Once used, the catheter is discarded.
Since balloon-tipped catheters were first introduced during the mid-70's, other types of catheters have been designed for various other types of surgical procedures. For instance, catheters having a balloon tip with a large profile were developed for valvuloplasty procedures. Angiographic catheters with one lumen were developed to diagnose the existence of stenotic lesions in the arteries while guide catheters are used to position other types of catheters within the body.
The number of procedures using different types of catheters increases each year. During 1991 alone the number of procedures worldwide approximated one billion. The cost of the various types of catheters used in these procedures represents a significant portion of the overall cost of the operation. For instance, balloon-tipped catheters used in angioplasty and valvuloplasty procedures cost approximately $600.00/each with the cost increasing each year as variations and improvements are developed. The ability to reprocess and reuse catheters would provide a decided advantage by helping to control the spiraling cost of the surgical procedures utilizing them.
Attempts to develop a system to reprocess catheters have met with limited success. Manual reprocessing of catheters has provided a limited means for reprocessing and reusing the catheters. However, manual reprocessing is prone to human error and the sterility critical to a successful operation cannot be guaranteed. In addition, manual systems cannot guarantee the integrity of the catheter once it is reprocessed. Further, manual systems also fail to provide the necessary identification, monitoring, control and versatility required to produce a safe and efficient catheter reprocessing system.
U.S. Pat. No. 4,721,123 assigned to the same assignee of the present invention describes a method and apparatus for reprocessing catheters that overcomes many of the problems associated with manual reprocessing. However, the catheter sterilizing cassette described therein is costly to manufacture and awkward to use. Further, the reprocessed catheters must be used immediately because it is difficult to maintain pressure within the cassette. Consequently, the sterility of the cassette and the catheter contained therein cannot be maintained for long periods of time during storage. Moreover, the reprocessing cycle takes hours to accomplish because the system is unable to use advanced chemical sterilants that require heating. A new and improved catheter reprocessing and sterilizing system is needed to overcome these problems.